Press Your Buttons Now! - We look back at talent shows of yesteryear.

When Will I Be Famous? follows in a long line of talent shows on television, but did you know..?

The best-remembered talent show in the UK is Opportunity Knocks, created and presented by Hughie Green.

Opportunity Knocks started as a radio show on the BBC Light Programme, before moving to Radio Luxemburg and then to ITV, where it ran (after one series in 1956) from 1961-1978.

The winner of each heat was decided by a postal vote. With the result announced at the start of the next show.

Although, it didn't count, the audience's reaction to each act was shown on a clapometer - a moving pointer supposedly determined by the noise they generated. In reality, this involved a studio hand guessing and moving the pointer accordingly.

Famous acts that appeared on the show included Bonnie Langford, Les Dawson, Little and Large, Max Boyce, Freddie Starr and Lena Zavaroni.

Hi-de-Hi! actress Su Pollard was beaten on the show by a dog.

Hughie Green's catchphrase was 'and I mean that most sincerely folks'.

The BBC revived the show in 1987 as Bob Monkhouse Says Opportunity Knocks with Kiki Dee's 'Star' used as the theme tune.

Bob's catchphrase was 'When opportunity comes your way... don't knock it'.

Les Dawson replaced Bob for one further series in 1990.

New Faces is also fondly remembered. This show ran on ITV in the 70s and was originally presented by Derek Hobson.

The show was a tougher version of its rival, with a panel of judges deciding the contestants' fate, marking them out of ten in various categories.

Sixties singer Mickie Most, and Neighbours and Crossroads theme tune composer Tony Hatch sat on the panel.

Famous contestants included Lenny Henry, Victoria Wood, Michael Barrymore, Joe Pasquale, Les Dennis, Gary Wilmot, Jim Davidson and the Chuckle Brothers.

Former winner Marti Caine presented a revival of the show in the 80s. The show became famous for Caine shouting 'Press your buttons now!' and for the harsh put-downs of TV critic Nina Myskow.

Pre-Take That, Gary Barlow wrote and performed an entry in the 1986 BBC Carol Competition, an annual talent contest for choir boy and girls.

Another talent show for the kids was Saturday Superstore's Search for a Superstar. Who can forget Claire and Friends, who sang It's Orrible Being in Love(When yer Eight and a Half)? The song won the competition and went to number 13 in the charts, unlucky for us.

In recent years the talent show has been revamped with celebrities trained to perform and face a panel of judges and a public vote. The most successful of these has been Strictly Come Dancing.

Shows such as Strictly Dance Fever and How Do You Solve a Problem Like Maria? have recently featured the return of total unknowns to the spotlight, all vywing for fame.